/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.room.writer

import androidx.room.compiler.codegen.VisibilityModifier
import androidx.room.compiler.codegen.XFunSpec
import androidx.room.compiler.codegen.XFunSpec.Builder.Companion.addStatement
import androidx.room.compiler.codegen.XTypeSpec
import androidx.room.ext.CommonTypeNames
import androidx.room.ext.RoomTypeNames
import androidx.room.ext.SQLiteDriverTypeNames
import androidx.room.ext.SupportDbTypeNames
import androidx.room.solver.CodeGenScope
import androidx.room.vo.FieldWithIndex
import androidx.room.vo.Fields
import androidx.room.vo.Pojo
import androidx.room.vo.ShortcutEntity
import androidx.room.vo.columnNames

class EntityUpdateAdapterWriter
private constructor(
    val tableName: String,
    val pojo: Pojo,
    val primaryKeyFields: Fields,
    val onConflict: String
) {
    companion object {
        fun create(entity: ShortcutEntity, onConflict: String) =
            EntityUpdateAdapterWriter(
                tableName = entity.tableName,
                pojo = entity.pojo,
                primaryKeyFields = entity.primaryKey.fields,
                onConflict = onConflict
            )
    }

    fun createAnonymous(typeWriter: TypeWriter, dbParam: String, useDriverApi: Boolean): XTypeSpec {
        return if (useDriverApi) {
                XTypeSpec.anonymousClassBuilder(typeWriter.codeLanguage)
            } else {
                XTypeSpec.anonymousClassBuilder(typeWriter.codeLanguage, "%L", dbParam)
            }
            .apply {
                superclass(
                    if (useDriverApi) {
                        RoomTypeNames.DELETE_OR_UPDATE_ADAPTER.parametrizedBy(pojo.typeName)
                    } else {
                        RoomTypeNames.DELETE_OR_UPDATE_ADAPTER_COMPAT.parametrizedBy(pojo.typeName)
                    }
                )
                addFunction(
                    XFunSpec.builder(
                            language = language,
                            name = "createQuery",
                            visibility = VisibilityModifier.PROTECTED,
                            isOverride = true
                        )
                        .apply {
                            returns(CommonTypeNames.STRING)
                            val pojoCols = pojo.columnNames.joinToString(",") { "`$it` = ?" }
                            val pkFieldsCols =
                                primaryKeyFields.columnNames.joinToString(" AND ") { "`$it` = ?" }
                            val query = buildString {
                                if (onConflict.isNotEmpty()) {
                                    append("UPDATE OR $onConflict `$tableName` SET")
                                } else {
                                    append("UPDATE `$tableName` SET")
                                }
                                append(" $pojoCols")
                                append(" WHERE")
                                append(" $pkFieldsCols")
                            }
                            addStatement("return %S", query)
                        }
                        .build()
                )
                addFunction(
                    XFunSpec.builder(
                            language = language,
                            name = "bind",
                            visibility = VisibilityModifier.PROTECTED,
                            isOverride = true
                        )
                        .apply {
                            val stmtParam = "statement"
                            addParameter(
                                if (useDriverApi) {
                                    SQLiteDriverTypeNames.STATEMENT
                                } else {
                                    SupportDbTypeNames.SQLITE_STMT
                                },
                                stmtParam
                            )
                            val entityParam = "entity"
                            addParameter(pojo.typeName, entityParam)
                            val mappedField = FieldWithIndex.byOrder(pojo.fields)
                            val bindScope =
                                CodeGenScope(writer = typeWriter, useDriverApi = useDriverApi)
                            FieldReadWriteWriter.bindToStatement(
                                ownerVar = entityParam,
                                stmtParamVar = stmtParam,
                                fieldsWithIndices = mappedField,
                                scope = bindScope
                            )
                            val pkeyStart = pojo.fields.size
                            val mappedPrimaryKeys =
                                primaryKeyFields.mapIndexed { index, field ->
                                    FieldWithIndex(
                                        field = field,
                                        indexVar = "${pkeyStart + index + 1}",
                                        alwaysExists = true
                                    )
                                }
                            FieldReadWriteWriter.bindToStatement(
                                ownerVar = entityParam,
                                stmtParamVar = stmtParam,
                                fieldsWithIndices = mappedPrimaryKeys,
                                scope = bindScope
                            )
                            addCode(bindScope.generate())
                        }
                        .build()
                )
            }
            .build()
    }
}
